Difference Between Low GI and High GI

Glycemic Index abbreviated as GI is an index which shows the rate of blood sugar level rising after consuming a particular meal. The standard used is pure glucose, and it is given the value of 100 by default. All other food GI’s are measured relative to this. For ease of application 3 main ranges of GI are identified. Low GI (55 and less), Medium GI (56-69), and High GI (70 and above) are the 3 main classes. Although a food is given a particular GI value, it may deviate in a range due to various reasons like batch or crop, methods of processing, packing and storing etc. This discussion is limited to Low GI and High GI.

Low Glycemic Index (Low GI)

Low GI foods have Glycemic Index 55 or less. The meaning of “Low GI” is that when these foods are consumed the rate of blood sugar level increases at a slower rate. This happens because low GI foods release glucose slowly and steadily with time. It allows body to use the energy efficiently, and since there is no excess energy it is not required to be stored. Therefore, no unhealthy weight gain will result.

Low GI foods are highly recommendable to people suffering from Insulin resistance, diabetes, or hyperglycemia because they essentially need to maintain low blood glucose levels and low variation. Most fresh fruits and vegetables are low GI. Potatoes, sweet potatoes, beetroot etc. are exceptions. Beans such as kidney beans, lentils, soy, peanut, chickpea, walnut, and whole grains are very good examples for low GI foods. Low GI does not necessarily mean that the carbohydrate content is low. In order to take this in to account one should know the value of glycemic load of a certain food item.

High Glycemic Index (High GI)

High GI foods have Glycemic index 70 and higher. The meaning of high GI is that when these foods are taken the blood glucose levels rise very rapidly. This is an intense fluctuation of blood glucose level also called a “sugar spike”. Due to the rapid introduction of glucose body cannot use the load very efficiently and tends to store it as glycogen or fat. This results in unhealthy weight gain.

Also, high GI food consumption is dangerous to people suffering from diabetes, hyperglycemia and insulin resistance. However it is advisable that people suffering from hypoglycemia (low blood sugar) should take more of high GI food in their diets in order to maintain the healthy blood glucose levels. High GI foods are also used in situations where energy is needed rapidly E.g. after exercising, running a race etc. Food such as potatoes, white bread, white rice, extruded snacks, and breakfast cereals are popular high GI foods. Intake of high GI food can damage the liver and cardiovascular system in the long run. In some incidents eyes and brains etc. are also affected.